Riyad as-Salihin 4:5

Ya'ish bin Tikhfah Al-Ghifari (May Allah be pleased with him) reported:

My father said: I was lying down on my belly in the mosque when someone shook me with his foot and said, "Lying down this way is disapproved by Allah." I looked up and saw that it was Messenger of Allah (ﷺ). [Abu Dawud] .